Regenerative purging system for refrigerating plants



Feb'. 15,1927. 1,617,631-

N. H. GAY

REGENERATI VE PURGING SYSTEM FOR REFRIGERATING PLANTS Filed Feb. 1'7, 1926 P r orFicE.

NORMAN H. GAY, 015 LOS ANGELES, CAL II E ORNIA.

REGENERATIVE PURGING SYSTEM FOR REFRIGERATIN G PLANTS. I

Application filed February 17, 1926. Serial No. ss,s24.

This invention relates to improvements in refrigerating plants and more particularly-to purging systems for the same.

One object of this invention isto provide a means for separating foreign ases and 011 from the refrigerant circuit an to separate these undesired substances from the refrig erant medium in substantial freedom. therefrom, whereby such substances may be withdrawn without loss of refrigerant medium.

Another object is to accomplish this separation without the use of external heat and cold or the diversion of a part of the liquid refrigerant for the purpose, and by the mutual and regenerative action of, the two substances one upon another to separate the refrigerant therefrom.

Further objects will appear in the course oi the following specification, taken in conjunction with the accompanying drawing which represents a diagrammatical layout of a refrigerating plant embodying the presentregenerative urging system.

In this p ant, the usual compressor 10 delivers the warm com ressed gas through a dischar e valve 11 and the discharge line 12 to a hig pressure oil trap 13, whence the gas flows through discharge pi e 14 to the inlet header or manifold 15 of t e condenser 16. The flow of gas to the condenser is regulated by a condenser inlet valve 17. The condenser 16 may be of any appro riate design and usually comprises a num er of pipes through which the as may flow and which are externally coole by any suitable medium such as water, so that the refrigerant as is condensed and liquefied thereinand elivered in such condition to the outlet manifold or header 18, whence it flows throu h a liquid valve 19 and the gravity liqui line' 20 into the liquid receiver 21. -lhe liquid refrigerant collects in the bottom of this receiver and is drawn ofl therefrom through the liquid line 22 which is reulated by a king valve23, and passes to the iquid line 24 and through a liquid-stop valve 25 into the liquid cooling coil 26 and thenc throu h the liquid line 27 and, the expansion va ve 28 to the gas separating chamber :29. The liquid-drop leg 30 from this; chamber 29 leads to a low pressure oil trap '31, from which the refrigerant mayvflow throu h a pipe 32 and the liquid valve 33 into the iquid header.

34 and thence into the refrigerating coil 35 which constitutes the means of cooling the ice freezing tank, ice box or other chamber to the compressor 10. This constitutes the nor-,

mal circuit of the refrigerant medium through the plant. v

The gas separating chamber 29 and the hquld separating chamber 39 are in free communication with each other, so that the gases separated in chamber 29 pass upward into chamber 39, and the liquids separated in chamber 39 pass downward into the cham ber 29.

It is necessary to employ lubricatin oil within the compressor 10 and it has een found by experience'that a considerable portion of this oil is carried along with the outgoing warm gases through the discharge valve 11 and pipe 12; A portion of this oil 18 separated in the high pressure oil trap 13 and collects in the bottom thereof. This trap 13 is exposed to the atmosphere and is cooled thereby. The separated oil drains into the high'pressure oil line 43 andanay be relieved through the manually operated valve 44 into the oil bus line 45 and thence through the oil feeding Valve 45 into the regenerator casing 46. The oil in passing the valve 44 loses its high pressure and is reduced tothe low pressure prevailing in the oil bus line 45; during which reduction, the refrigerant contained therein is partly given off and cools the oil:

A further portion of the oil is carried along into the condenser 16, and trickles downward through its pipes and the header 18 and along the pipe 20 until it is received in the liquid receiver 21. Since the specific gravity of this oil is greater than the specific gravity of the liquefied refrigerant medium, the oil will pass to the bottom of the receiver and flow therealong until it is stopped by the dam or bafliej47 arranged near, one'end' of the receiver 21, in front of the inlet to the liquid line 22. The oil ac-' cumulating in the receiver 21 drains into the oil separator drum 48 and may be relieved therefrom through the oil" purging valve 49 which leads to the cold oil pipe 50 which opens into the oil bus line 45 and hence to the iegenerator casing 46. The oil 1 ing valve 51 into the oil bus line 45 and Y in passing the valve 49 loses its high pressure and is reduced to the low pressure prevailing in the oil bus line 45; during which reduction, the liquid refrigerant contained therein is partly given off and cools the oil. Any remaining oil carried along with the refrigerant medium enters the gas separating -chamber 29 and passes downward through the pipe 30 into the low pressure oil trap 31 which is preferably heat-insulated. Oil carried through the valve 33 into the chilling coil 35 and held within this coil will establish a reflux into the liquid header 34 when the system is shut down at any interval, and thence flow back into the bottom of the low pressure oil trap 31 which serves as a drain, from which the oil may be relieved through the low pressure trap purgthence into the regenerator casing 46.

Any foreign gases such as air or the like.

which may be contained within the system and which are not condensed at the temperature of the condenser 16 pass along and,

mingled with varying proportions of the refrigerant gas, accumulate inJhe outlet header 18; the foreign gases which are lighter than the refrigerant gas, accumulate in the upper portion thereof, from which they may be drawn off with admixed refrigerant medium through the equalizing line valve 52 into the gas purging or equalizing line 53 which opens into the regeneratorcondensing coil 54 which is contained within the regenerator casing 46. The foreign gases which are heavier than the refrigerant gas accumulate in the lower portion of the outlet header 18, from which they automatically pass downward through liquid valve 19 and gravity liquid line 20 into the upper part of liquid receiver 21; from which they are drawn through valve 55 into coil 54. It will be noted that by manually manipulating valves 52 and=55 either the lighter foreign gas may be taken from the top of the outlet header, or the heavier foreign gas 1 may be taken from the top of the receiver at the option of the operator. The mingled foreign gases from the receptacles 18 and 21 are at a relatively high pressure and temperature but still contain gaseous refrigerant mixed therewith.

The regenerator coil 54 is optionally in communication through valve "with the liquid receiver 21, so that liquid refrigerant forming in coil 54 can be withdrawn by gravity into receiver 21 and is thus re' claimed. .The upper end of the coil 54 is connected through a foul gas purging valve 55 with a foul gas purging vent-pipe 56.

The mingled oil from the receptacles 13, 48, and 31 is at a relatively low pressure and "temperature, but still contains liquid refrigerant mixed therewith.

cation through a regenerator suction valve 57 and the regenerator suction line 58 with the suction line 40 of the refrigerating plant, so that any gaseous refrigerant formingin .the regenerator casing will pass back into the refrigerating system and thus be reclaimed. The lower part of the regenerator casing 46 is in communication through the oil purging valve 59 and the pipe 60 with a portable oil receptacle (not illustrated).

It will be noted that liquid'refrigerant may be likewise drawn 011' through a valve 61 and pipe 62 for any other use, and it and the noncondensible foreign gases are separated in the header 18 as set forth above and contain a varying quantity of the refrigerant medium in gaseous form, and may flow through the equalizing line 53 or through receiver and connection 55 to the regenerator condensing coil 54. Theliquid refrigerant mingled with oil passes into the receiver, and the oil is partly separated as described above, but always'contains a quantity of liquid" refrigerant. Likewise,

the oil separated in the low pressure trap 31 Willvcon-tain a guantlty of refrlgerant' therein. The mix oil and refrigera'ntis withdrawn from the several traps through their respective valves into the oil bus line 45 and thence into the re enerator casing 46 through the valve 45. gince the oil' entering the casing is mingled with liquid refrigerant irrespective of whether it comes from the-high pressure oil trap 13, the receiver oil trap 48, 'or ihe low pressure oil trap 31, the oil will give ofi this refrigerant in the form of a gas by evaporation-of same under the low pressures prevailing,- and the evaporation of this liquid refrigerant .will cool the oil to the temperature'jat which the refrigerant is evaporating, which will be considerably lower than the condensing temperature of the refrigerant under the pressure prevailing in the coil 54. This gasifying refrigerant from the oil returns through the pipe 58 when" the valve 57 is open into ,the return pipe 40. Since the foreign gases are permitted to flow through the valves 52 or 55 into the coil 54, hearing with them their content of gaseous refrigerant, they are exposed to a temperature within the regenerator casing. 46 which is considerably lower than the condensing point of the gaseoi is'refrigerant at theparwise separated. As the plant continues to work, the foreign gases which are not condensed will accumulate in the coil 54 and especially in the upper part thereof. From time to time the foreign gases are slowly drawn off through the pipe 56 by slightly opening valve 55 during which operation very little, if any, refrigerant will escape.

On the other hand, the oil within the casing 46 of the regenerator delivers its refrigerant in a gaseous condition as set forth above, and settles to the bottom of the cas-' ing 46. From time to time, as the oil accumulates within this casing, the oil feeding valve which delivers oil to the casing 46 may be closed and the outlet valve 59 opened, so that the oil is permitted to pass through the pipe 60 to an oil storage receptacle from whlch it may be removed and disposed of or if in suitable condition retained for further use in the compressor, or other portions of the plant.

By'this method of o erating and the apparatus for accomplishing it, the refrigerant contained in the foreign non-condensible gases is recovered by the utilization of the admixture of refrigerant contained in the. trapped oil, so that there is substantially no loss of refrigerant from' the system as a whole, and the foreign non-condensible gases and the oil are each separated in a relatively pure condition, without the expenditure of external energy for heating or cooling the same.

It is obvious that the invention is not specific method of employment but that 'these may be modified within the scope 0 the appended claims.

What is claimed as new is:

1. In a refrigerating plant, a compressor, a condenser, an expansion valve, a refrigerating coil, conduits connecting said elements, oil traps disposed between said. condenser and said refrigerating coil, a regenerator casing in communication with said oil traps to receive oil therefrom, a gas suction pipe communicating between said casing andthe intake of said compressor, a condensing coil in said casing and in communication with the outlet from said condenser, a gas purging line from said condenser to said condens'ing coil, and afoul gas purging valve to relieve foul gases from said coil.

r 2. In a refrigerating plant, a compressor,

a condenser connected'with' said compressor,-a high pressure oil trap in said connection, a gravity liquid line from said condenser, a liquid receiver connected to said gravity line, a liquid line from said receiver,

an expansion valve in said liquid line, a refrigerating coil connection to said liquid line beyond said expansion valve, a main suction line from said refrigerating coil to said compressor, an oil drum in communication with the bottom of said receiver, an oil trap and drain at the inlet to'said refrigerating coil, a regenerator casing, conduits commu-.

nicating between said oil traps-and drum and said casing, at the lower end of said casing a valve for'the' removal of the oil, remaining after regeneration, a regenerator suction line from said casing to said main suction line, a gas pressure equalizing and purging pipe communicating between the outlet end. of said condenser and the top of said receiver, a vertical condensing coil in said casing in communication with said equalizing'pipe at its lower end, and a foul gas withdrawal pipe and valve in communication with said coil at its upper end.

A purging regenerato'r for a refrigerating plant comprising a casing adapted to receive oil-mixed with refrigerant from said plant, a vertical coil-in said casing, a gas conduit from the outlet of the condenser of the plant to the lower end of said coil, a coman oil withdrawal pipe at the bottom of said casing, and a foul gas purging connection at the upper end ofsaid coil.

4. In a refrigerating plant having a compressor-condenser-expander circuit, means for partially separatln oil from refrigerantby gravity, a heat-exc ange vessel having a high pressure and a low ,pressure compartment, a conduit to bring the partially separated oil into the low pressure compartment, means for partially separating foul gas from refrigerant, a conduit to bring the partially separated foul gas into the high pressure compartment, whereby the exchange of'heat between such partially separated oil and foul gas will effect a separation of refrigerant therefrom, means 'to return the separated refrigerant into the circuit, and means for collectingdand; removing the oil and foul gas.

5. The method of urging a refrigerating plant of oiland fou gas, which consists in partially separating the oil in the high pressure portion of the plant fronithe refrigerant, reducing the pressure upon the artially separated" mixture of oil and re rigerant whereby to evaporate a portion of the refrigerant contained therein, partially separating the foul gas from the refrigerant 1n the high pressure portion of the plant, effecting a heat exchange between the two mixtures whereby to cool the refrigerant contained in the foul gas mixture to liquefy the same and to heat the refrigerant contained in the oil .mixture whereby to volatilize the same, re-

turningithe volatilized refrigerant into the system at the low pressure side, and returning the. liquefied refrigerant into the system at the high pressure side.

6. The method ofpurging a refrigerating plant of oil, which consists in partially separating the oil from the refrigerant in the high pressure portion of the plant, reducing the pressure upon the partially separated mixture whereby to evaporate a portion of the refrigerant contained therein, separating the foul gases from the high pressure portion of the plant, and effecting a heat exchange between the foul gases and the mixture to evaporate the residuum of refrigerant therefrom.

7. The method of purging a refr gerating with the partially separated mixture of foul v gas and refrigerant whereby to liquefy the refrigerant therein, returmng the refrlgerant for circulation in the plant, and removing the foul gases therefrom. v

In testimony whereof, I aflix my signature.

NORMAN H. GAY. 

